The iPad went on sale nationwide at 9 a.m. on Saturday. As of midnight on Saturday, the company said it had sold 300,000 iPads, including pre-orders. Apple did not provide sales numbers for Sunday.

Customers lined up outside Apple retail stores in cities across the nation early Saturday morning to be among the first to buy the iPad, which starts at $499. The device combines features of Apple's popular iPhone with the power of a laptop computer.

Expectations for the iPad's debut varied widely, with some forecasts calling for sales in the range of 700,000 in the first day. But analysts said first-day sales do not necessarily reflect how the iPad will do over the long run.

"We believe iPad has potential to become a high volume device as it could revolutionize publishing and gaming markets, not to mention mobile computing itself," Shaw Wu, analyst at Kaufman Brothers, wrote in a research report. "Our concern is that it may take several quarters to several years to play out."

Wu expects Apple to sell 10 million iPads over the next 12 months, with sales climbing as high as 20 million in 2011.

While the launch was not as spectacular as some had anticipated, many Wall Street analysts raised price targets for Apple stock Monday.

Mark Moskowitz, an analyst at JP Morgan, now expects shares of Apple to reach $305 this year, up from a previous estimate of $240, based on strong demand for Macs and iPhones, as well as interest in the iPad.

"There will be the Apple faithful and the early adopters who support the initial roll-out," Moskowitz wrote in a research report. "But we do not expect a scenario whereby units rise to more than 2 million per quarter in the first generation."

Moskowitz estimates Apple will sell about 4.8 million iPads in the next 12 months.

The Los Angeles city attorney is suing four major retailers over claims that they deliberately inflated the original price on some items that misled customers into thinking they were getting a better deal. More